Improvement in packing projectiles for rifled ordnance



2 Sheets-Sheet 1 J. ABSTERDAM.

Projectile.

Patented Feb. 23, ,1864.

, i4 'izqesses 6%WCZ) fi/ N.PE1'ERSv PHOTO LT WASHINGTON D C J. ABSTERDAM,

Projectile.

lUNirnn Starts aren't tries.

JOHN ABSTERDAM, OF NEW YORK, N. Y.

IMPROVEMENT IN PACKING PROJECTILES FOPl RIFLED ORDNANCE.

Specification forming part of Letters Patent No. muses, dated February 23, 1864.

To all whom it may concern Beit known thatI, J oHNABsrE RDAM, scientific and mechanical engineer, of the city, county, and State of New York, have invented a new and useful Projectile for Rifled Gannon; and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon, in which- Figure 1 represents a perspective view of my projectile ready for firing. Fig. 2 represents a longitudinal section of my projectile with percussion-fuse. Fig. 3 represents alongitudin al section of my projectile with time-fuse. Fig. 4 represents a transverse section of my projectile. Fig. 5 represents the end of the expanding cup of my projectile.

A is the projectile 5 B, the expanding cup; E, the anti-friction bands; D, the percussionfuse; F, the time-fuse.

The nature of my invention consists in constructing a projectile for rifle-cannons with one or more bands or bearings of an anti-friction metal or alloy that expands by cooling, or made of a metal or composition that does not contract in cooling.

It consists, second, in sawingthe sides of the expanding cup diagonally to the axis of the projectile, in order to facilitate the expanding of the metal, at the same time preventing the escape of gas through the cuts in their being closed by the explosion of the charge when the gun is fired.

To enable others skilled in the art to make and use my invention, I will describe its construction and operation.

I make my projectile-cylinder conical in shape, or I make it any other desired form or shape. I cast it with one or more circular cavities running around its cylindrical part perpendicular to the axis of the projectile, as seen at E. These cavities I afterward fill with an anti-friction metal or alloy, which expands in cooling, or at least it does not contract or shrink in cooling. Before filling the cavities with the anti-friction metal I grind the cylindrical part of the projectile on an emery-wheel to admit of its passing through the cylindergage, and in order to cast the bands I place the projectile upright into the cylinder-gage. I then fill the cavities E around the projectile with the anti-friction metal, which forms its surface against the sides of the bore of the gage, the metal not shrinking in cooling. The bands E are exactly of the same diameter of the bore of the gage. The bands thus formed project a very little beyond the surface of the projectile A, forming the bearing-surface for the projectile while in the bore of the gun.

There is no necessity of turning or planing my projectile, the bearing-surface of the antifriction bands removing the necessity of its being turned or planed, as is ordinarily the case with rifle-cannon projectiles.

In forming the bearing-surface of my projectile with a metal that expands in cooling orwith a metal that does not shrink in cooling, I obtain projectiles all of one exact caliber or gage, every projectile having one exact windage, enabling the gunner to fire with more accuracy than could be done with projectiles of different windages.

The difference between the diameter of the projectile A and the diameter of the bands E is only that the projectile passes freely through the cylinder-gage, and the bands will not pass through the gage except in being forced through by pressure. The anti-friction metal being the bearing-surface, the projectile does not wear the surface of the bore of the gun, which is of a great importance for steel and bronze cannons.

I cast my projectile with a rabbet, P, having several sides, each side tapering toward the body of the projectile. I make each side of the rabbet concave, or I foil the sides with cavities, as seen at u, about which I cast the soft metal B for taking the grooves of the gun. The shape and cavities of the rabbet give the expanding metalB an additional hold to prevent its being torn off by torsion while passing through the grooves of the gun. I saw the end of the expanding-cup B in several cuts diagonally to the axis of the projectile, as seen at m, so to facilitate the expanding of the metal, and at the same time preventing the escape of gas through the cuts m in their being closed by the explosion of the charge in firing the gun.

The device which I employ for exploding the projectile, when a percussion-fuse is required, consists of a percussionfuse, D, hav in g inserted therein aplunger, a a, surmounted metals.

by a cone, 0 e, supplied with a musket-cap, d. The plunger is made with a tail, K, which, when closed, is a metallic tube, h, out along several of its right-line elements. Then I insert the plunger in the fuse-plug b, the tail passes through the bottom of the plug at I, and is afterward expanded bypressing into the end on the tube a conical wedge. The shock required to dislodge the plunger a a may be regulated by increasing or diminishing the expansion of the tube h. I expand the tube after inserting the plunger in the fuse-plug, lapping the several strips of the tube over the lever end of the fuse-plug, forming series of open springs, which compensate the plunger so that it may resist any given fall of the projectile which may be required in order to prevent explosion from a fall of the projectile before .firing the same. But in firing, the impact of the projectile dislodges the plunger a a and explodes the cap d by being thrown against the screw-plug 0 in the end of the shot.

The time-fuse F which I employ consists in a fuse-plug, g, for a common paper fuse, H, having two cylindrical holes, I, one on each side ofthe fuse. (These holes do not penetrate through the bottom of the plug.) I ignite the paper fuse with two friction-pr1mers,s, which I hang in the cylindrical holes I in the fuse-plug 9, one on each side of the fuse H.

v The primers 8 which I employ are small and straight, having a small lead tube,.t, attached to the end of the fricionwire, which acts as a weight, and the primers are exploded by the inertia of the lead tube t, which is heavy enough to cause the friction-wire to move rearward in the act of firing the gun. The wire in moving rearward produces sufficient friction to ignite the powder of the primers, thereby throwing two jets of flame, 0 0, on the head of the paper fuse I1. I protect the fuse from the contact of the atmosphere by means of a cover, f, screwed on the head of the fuse-plug g, and I insert a leather disk, 2), within the cover, so to make a tight joint, in order to keep the interior of the projectile perfectly dry.

The metal or alloy which I generally employ for the bearing-surface of my proj ectile. is composed of nine parts of lead, two of antimony, and one of bismuth. This metal expands in cooling. I also employ the metal now used for stereotypeplates, which is composed of nine parts lead, two of antimony, and two of bismuth, by adding to it nine parts of lead and two of antimony.

I do not confine myself to the use of these Other alloys may produce the same result.

The metal which I employ for the expandin g cup for small caliber is composed of fifteen parts of lead and one part of antimony, and for large calibers I employ brass.

The cup and bands of my projectile do not lead the grooves of the gun.

It is a well-known fact that it is impossible to cast projectiles all of one exact caliber or gage, nor can shells be cast with sides without danger of explosion.

of one exact thickness; and in order to obtain projectiles of a uniform caliber some manufacturers have to resort to turning and others to planing, but no one yet ap pears to have taken into consideration which side of the shell will be the most reduced by turning or planingwhether the thickest or the thinnest side will be the most reduced. If the thickest side of the projectile is the most reduced, then the center of gravity will get toward the axis of the projectile, but if the thinnest side is the most reduced the center of gravity will be farther separated from the axis of the projectile and a shell so turned will be less accurate than in. its rough state. So far as the uniformity of caliber is concerned, it is impossible to obtain projectiles all of one exact caliber by simply turning them. It can only be obtained by turning and finishing the cylindrical part of the projectile as accurate as the journal of a shaft or axle-a turning and finishing too expensive to be entertained for supplying an army and navy of a great nation with such projectiles. Therefore, in order to obtain 'projectiles all of one exact caliber or gage without the expense of turning or planing, without machinery or machine'shops, I have invented my projectile, whereby a great army and navy can be supplied with accurate projectiles as fast as they can be cast.

My substitute for turning or planing is simple. I simply introduce the projectile upright into the cylinder-gage. I then pour the melted alloy into the circular cavities, and the alloy expanding in cooling forms its surface against the sides of the bore of the I then press the projectile out of the gage by means of a screw-bolt, and on account of the meta. expanding in cooling, the bands proj eetin g a very little beyond the surface of the cylindrical part of the body of the projectile, they become the bearingsurface for the shot. The projectiles so prepared are all ofone exact caliber or gage, which is of the utmost importance for accurate firing. When the grooves of the gun are sufficiently deep, I cast the bands with projections to fit easily into the grooves of the gun. In that case I dispense with the expanding metal at the base of the projectile.

Projectiles all of one exact caliber, having all one exact wind age, will describe the same trajectory, but projectiles of different calibers, havingdifferent windages, will describe different trajectories. The first will fire with accuracy, the latter with uncertainty.

My percussion-fuse is safe and simple. A shell provided with this fuse may be let fall point down from the height of twelve feet The shell may be also put in the caisson point down without danger of explosion; but the plunger may be so regulated at pleasure to insure the explodin g of the shell when fired from the gun.

The plunger may be primed or not, just as desired. I have found in firing that the shell explodes Whether the plunger not.

My time-fuse is only the ordinary paper fuse now used in field service with the addition of a tight cover and some friction-primers to ignite the fuse. The cover protects the fuse from the action of the atmosphere in the flight of the projectile, allowing the fuse to burn with regularity, and before charging the shells it is also important to keep their interiors peris primed or fectly dry, which is accomplished by screwing down the tight cover.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. Constructing a projectile for rifle-cannon JOHN ABSTERDAM.

In presence oi JAMES NIRER, W. R. SLUYTER. 

